Vibratory gyroscope sensor

Abstract

A vibratory gyroscope sensor (1) comprising:a base (2),a resonator (3) that includes a central foot (30) by which the resonator (3) is attached to said base (2) and a sidewall (31) that rises from said foot (30) up to a free end edge (310) delimiting an opening,characterized in that said sidewall (31) has a proximal portion (311) that rises from and around said foot (30) as well as a distal portion (312), generally cylindrical in shape, that extends in line with said proximal portion (311) up to said free end edge (310), said proximal portion (311) progressively widening from the foot (30) towards the distal portion (312).Gyroscope sensors

1 . A vibratory gyroscope sensor ( 1 ) comprising:
 a base ( 2 ),   a resonator ( 3 ) that includes a central foot ( 30 ) by which the resonator ( 3 ) is attached to said base ( 2 ) and a sidewall ( 31 ) that rises from said foot ( 30 ) up to a free end edge ( 310 ) delimiting an opening,   characterized in that said sidewall ( 31 ) has a proximal portion ( 311 ) that rises from and around said foot ( 30 ) as well as a distal portion ( 312 ), generally cylindrical in shape, that extends in line with said proximal portion ( 311 ) up to said free end edge ( 310 ), said proximal portion ( 311 ) progressively widening from the foot ( 30 ) towards the distal portion ( 312 ).   
     
     
         2 . The vibratory gyroscope sensor ( 1 ) according to  claim 1 , characterized in that said proximal portion ( 311 ) has a straight circular frustoconical profile. 
     
     
         3 . The vibratory gyroscope sensor ( 1 ) according to  claim 2 , characterized in that said cone has a symmetry axis and is inclined with respect to a plane (P) perpendicular to said symmetry axis by an angle (α) between 10 and 45°, preferably between 25 and 35°, even more preferentially equal to about 30°. 
     
     
         4 . The vibratory gyroscope sensor ( 1 ) according to  claim 1 , characterized in that said proximal portion ( 311 ) extends between, on the one hand, a first circular edge ( 3110 ) connected to said foot ( 30 ), and on the other hand, a second circular edge ( 3111 ) connected to said distal portion ( 312 ) and from which from which the latter rises up to said free end edge ( 310 ), said first and second circular edges ( 3110 ,  3111 ) having such a first and a second diameter, respectively, that said first diameter represents at most 60% of the second diameter, preferably at most 50% of the second diameter, said proximal portion ( 311 ) having an external face ( 311 A) that extends on the side of the base ( 2 ) and an opposite, internal face ( 311 B), said foot ( 30 ) comprising an external portion ( 302 ) protruding on the side of the external face ( 311 A). 
     
     
         5 . The vibratory gyroscope sensor ( 1 ) according to  claim 4 , characterized in that said external portion ( 302 ) has a local cross-sectional restriction ( 302 A) forming a concave surface to which said external face ( 311 A) is connected. 
     
     
         6 . The vibratory gyroscope sensor ( 1 ) according to  claim 4 , characterized in that said foot ( 30 ) comprises an internal portion ( 301 ) protruding on the side of said internal face ( 311 B), said resonator ( 3 ) comprising a connection fillet ( 5 ) that extends around said internal portion ( 301 ) to connect the latter to said internal face ( 311 B), said connection fillet ( 5 ) having for example a radius of curvature at least equal to 1 mm, preferably at least equal to 2 mm. 
     
     
         7 . The vibratory gyroscope sensor ( 1 ) according to  claim 1 , characterized in that said foot ( 30 ) has a massive and monolithic nature. 
     
     
         8 . The vibratory gyroscope sensor ( 1 ) according to  claim 1 , characterized in that said proximal portion ( 311 ) includes a plurality of arms ( 6 ,  7 ,  8 ,  9 ,  10 ,  11 ,  12 ,  13 ) separated from each other by clear spaces and arranged equiangularly around said foot ( 30 ), each of said arms ( 6 ,  7 ,  8 ,  9 ,  10 ,  11 ,  12 ,  13 ) extending longitudinally between a central end arranged on the side of the foot ( 30 ) and a peripheral end arranged on the side of the distal portion ( 312 ). 
     
     
         9 . The vibratory gyroscope sensor ( 1 ) according to  claim 8 , characterized in that each of said arms ( 6 ,  7 ,  8 ,  9 ,  10 ,  11 ,  12 ,  13 ) includes at least:
 a main section ( 6 A,  7 A,  8 A,  9 A,  10 A,  11 A,  12 A,  13 A), which extends from said central end,   and an end section ( 6 B,  7 B,  8 B,  9 B,  10 B,  11 B,  12 B,  13 B) of reduced cross-section with respect to that of the main section and that extends between the latter and said peripheral end.   
     
     
         10 . The vibratory gyroscope sensor ( 1 ) according to  claim 8 , characterized in that said proximal portion ( 311 ) comprises a first flange ( 25 ) that extends from and around said foot ( 30 ), each first end of each of said arms ( 6 ,  7 ,  8 ,  9 ,  10 ,  11 ,  12 ,  13 ) being integral with said first flange ( 25 ). 
     
     
         11 . The vibratory gyroscope sensor ( 1 ) according to  claim 8 , characterized in that said proximal portion ( 311 ) comprises a second flange ( 26 ) that extends from the distal portion ( 312 ) towards the inside of the resonator ( 3 ), each second end of each of said arms ( 6 ,  7 ,  8 ,  9 ,  10 ,  11 ,  12 ,  13 ) being integral with said second flange ( 26 ). 
     
     
         12 . The vibratory gyroscope sensor ( 1 ) according to  claim 1 , characterized in that it comprises a plurality of excitation devices attached to said proximal portion ( 311 ) to excite said resonator ( 3 ) into vibration, as well as a plurality of detection devices attached to said proximal portion ( 311 ) to detect vibrations of said resonator ( 3 ). 
     
     
         13 . The vibratory gyroscope sensor ( 1 ) according to  claim 8 , characterized in that said excitation devices and said detection devices are attached to said arms ( 6 ,  7 ,  8 ,  9 ,  10 ,  11 ,  12 ,  13 ). 
     
     
         14 . The vibratory gyroscope sensor ( 1 ) according to  claim 12 , characterized in that it comprises piezoelectric elements ( 14 ,  15 ,  16 ,  17 ,  18 ,  19 ,  20 ,  21 ,  22 ,  23 ,  24 ) that form said excitation devices and said detection devices. 
     
     
         15 . The vibratory gyroscope sensor ( 1 ) according  claim 14 , characterized in that it comprises conductive rods ( 40 ,  41 ,  42 ,  43 ,  44 ,  45 ,  46 ,  47 ) electrically connected to said piezoelectric elements ( 14 ,  15 ,  16 ,  17 ,  18 ,  19 ,  20 ,  21 ,  22 ,  23 ,  24 ) by micro-cables, each conductive rod ( 40 ,  41 ,  42 ,  43 ,  44 ,  45 ,  46 ,  47 ) being for example arranged in respective correspondence with one said clear spaces.